DE29722552U1 - Feather pad - Google Patents

Description

Meissner; B*oltb ^: & Partner

Law firm GbR

PO Box 860624 81633 Munich

04.12.1997

Trelleborg GmbH R/TRL-014-DE/G

Oderstrasse 76 RU/RU/dr

D-24539 Neumünster

Spring pad description

The present invention relates to a spring pad, in particular a spring pad for the spring bearing of the rear axle of a passenger car. The spring pad has a disk-shaped body made of elastomeric material and a reinforcing insert embedded in this elastomeric body.

Spring pads of this type are well known and serve to provide upper and lower support for a torsion spring, which is part of the rear axle suspension of a passenger car. The torsion spring is usually supported at the top in the wheel housing against the body, and at the bottom against a sheet metal plate attached to the outer tube of the spring or damper strut, with the spring pad then being placed between them as a noise-dampening element.

In known spring pads, the reinforcing insert embedded in the elastomer body is usually a metal plate that is completely covered by the elastomer material.

The disadvantages of such a known spring base are, depending on the type of metal used, the relatively high weight and the relatively complex manufacturing process, which makes the spring base unreasonably expensive. For such a manufacturing process, the metal part must be pre-phosphated and provided with an adhesion promoter so that a perfect chemical and physical bond with the elastomer material is guaranteed. In order to keep the weight of the spring base at least somewhat low,

Meissner, Bolte & Partner * ** "* * R/TLR-014-de/g

Aluminium is sometimes used for the reinforcement insert, although this has a lower rigidity than steel, for example.

The object of the present invention is to achieve a reduction in weight while simultaneously increasing the rigidity of the spring base.

This object is achieved according to the invention in a spring pad of the type mentioned at the outset in that the reinforcing insert is made of plastic.

The replacement of the metal reinforcement insert with a plastic reinforcement insert is the result of a long research and development activity, during which a suitable plastic granulate and an adequate connection between the elastomer material and the plastic had to be found. The spring base according to the invention is manufactured by injecting a specially composed elastomer mixture through a tool over the reinforcement insert made from a special plastic granulate and then vulcanizing it with the addition of heat and pressure. If there is a certain proportion of synthetic rubber (SBR = styrene-butadiene rubber) in the elastomer material, this process creates a mechanical connection between the elastomer and the plastic, which is referred to as interdiffusion of styrene heads. During this interdiffusion, the styrene heads of the synthetic rubber penetrate the surface of the plastic, which creates a firmly adhering connection after a certain cooling time.

The advantages of the spring pad according to the invention are in particular that it is lighter than the known spring pads and that the reinforcing insert can be embedded in the elastomeric material without any pre-treatment. This results in a relatively simple manufacturing process, which reduces manufacturing costs. In addition, the spring pad ensures

Meissner, Bolte & Partner r/tlr-014-de/g

Due to the plastic insert, it provides better acoustic decoupling of driving noise from the body and, due to its high rigidity, leads to an increase in static and dynamic load-bearing capacities.
5

Advantageous further developments of the invention are specified in the subclaims, according to which the reinforcing insert can be either a disk or a polygon and can be convex or concave.
10

In the following, a preferred embodiment of the invention is explained in more detail with reference to a drawing.

Show it:
15

Fig. 1 is a bottom view of a spring pad according to the invention ; and

Fig. 2 is a cross-section along the line A-A of Fig. 1.

Fig. 1 shows a bottom view of a spring pad, as provided in a number of four per vehicle for the spring bearings of the rear axle of a passenger car. The spring pad essentially consists of a disk-shaped, circular elastomer body 2, in which a reinforcing insert 4 in the form of a plastic disk is embedded (see Fig. 2). The underside of the spring pad has twelve recesses 1 and an equal number of water drainage grooves 3 to reduce its weight. In the center of the elastomer body 2, a guide nose 5 is formed, pointing towards the top of the spring pad, which forms a receiving space 10 for a metal cone that is accessible from the underside. Holes 6 in the recesses 1 extend through the lower half of the elastomer body 2 and have a manufacturing reason.

Fig. 2 shows a cross section along the line A-A of Fig. 1. This illustration shows the position of the plastic

Meissner, BoLTE & Partner "' * * R/TLR-014-DE/G

Reinforcing insert 4 and guide nose 5 are clearly visible. The reinforcing insert 4 is completely covered on the outside by the elastomer material. The guide nose 5 is used to position the torsion spring (not shown here) when assembling the spring or damper leg, in that the guide nose 5 engages axially in the torsion spring. A metal cone 7 is arranged in the receiving space 10 formed by the guide nose 5 for reinforcement, which in turn is reinforced by struts 8, 9. When producing the spring base, a specially composed rubber mixture is injected around the reinforcing insert 4, which is made from a special plastic granulate, using a tool and then vulcanized using heat and pressure.

Claims (5)

1. Spring pad, in particular for the spring bearing of the rear axle of a passenger car, with a disc-shaped body (2) made of elastomeric material and with a reinforcing insert (4) embedded in the elastomeric body (2), characterized in that the reinforcing insert (4) consists of plastic. 2. Spring base according to claim 1, characterized in that the reinforcing insert (4) is a disc. 3. Spring pad according to claim 1, characterized in that the reinforcing insert (4) has the shape of a polygon. 4. Spring pad according to claim 2 or 3, characterized in that the reinforcing insert (4) is convex. 5. Spring base according to claim 2 or 3, characterized in that the reinforcing insert (4) is concave.